Scientists at IOCB Prague are uncovering new details of gene transcription. They have identified a previously unknown molecular mechanism by which the transcription of genetic information from deoxyribonucleic acid (DNA) into ribonucleic acid (RNA) can be initiated. The researchers focused on a specific class of molecules known as alarmones, which are found in cells across a wide range of organisms and whose levels often increase under conditions of cellular stress. The results were published in the prestigious scientific journal Nature Chemical Biology.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_bc2bfffa6c.jpg" alt="IOCB Prague/Tomáš Belloň: Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription: Dr. Hana Cahová, head of the Chemical Biology of Nucleic Acids research group." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_bc2bfffa6c.jpg 234w," sizes="100vw" width="2000" height="1335"><div>Molecules of ribonucleic acid can carry a variety of chemical modifications at one end, known as caps. In eukaryotic organisms, including human cells, the best-known cap plays an important role in RNA stability and in regulating its subsequent fate. In recent years, however, it has become clear that alternative, non-canonical RNA caps also exist, although their formation and the mechanisms by which they are attached to RNA remain only partially understood. These include alarmone caps, formed by dinucleoside polyphosphate molecules, that protect cellular RNA at moments when the cell is under threat.In their study, <a target="_blank" rel="noopener noreferrer" href="https://cahova.group.uochb.cz/en">Dr. Hana Cahová</a> and colleagues examined bacterial RNA polymerase and investigated how this enzyme can initiate transcription using dinucleoside polyphosphates (NpNs) instead of the standard RNA building blocks. For the first time, the scientists described, at the atomic level, how RNA bearing an alarmone cap can be generated directly at the initiation of gene transcription. They also observed that NpNs bind through a different type of base pairing than is typically observed.The work was significantly shaped by Valentina Serianni from Hana Cahová’s team, who demonstrated the ability of dinucleoside polyphosphates to initiate gene transcription, and by Jana Škerlová, who focused on the structural analysis of RNA polymerase. Using cryogenic electron microscopy data, she showed how dinucleoside polyphosphate molecules bind within the active site of RNA polymerase – that is, the core of the enzyme where genetic information is transcribed. Together, their findings help to elucidate the processes that accompany the transcription of genetic information from DNA to RNA.Hana Cahová adds: “We’re describing something that truly occurs in cells and that we’re now able to observe directly at the level of individual molecules. This allows us to answer fundamental questions about cellular processes, such as how cells adapt to stress. RNA plays a central role in this, as it carries the cascade of information underlying any cellular response – for example, to threatening conditions caused by nutrient deprivation or temperature shock.”<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_2_0fe88ff9e9.jpg" alt="IOCB Prague/Tomáš Belloň: Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription: Dr. Tomáš Kouba, head of the Cryogenic Electron Microscopy core facility." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_2_0fe88ff9e9.jpg 234w," sizes="100vw" width="2000" height="1335"><div>Cryogenic electron microscopy (cryo-EM) was central to the project. This part of the work was led by Dr. Tomáš Kouba, one of the authors of the study. “Cryogenic electron microscopy allows us to freeze biological molecules in a state very close to their natural form and then determine their three-dimensional structure. This makes it possible to look directly into the active centers of enzymes and observe their function down to the atomic level,” he explains.Last year, IOCB Prague opened a new <a target="_blank" rel="noopener noreferrer" href="https://cryoem.group.uochb.cz/en">cryo-EM center</a> that is unique within the Czech research environment. State-of-the-art cryogenic electron microscopes are housed in a specially designed building and enable the study of biological processes with exceptional structural precision.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_3_4d881e7a58.jpg" alt="IOCB Prague: Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription: This work shows how NpnNs initiate bacterial transcription. Cryo-EM reveals how nucleobases pair with the template: one in canonical and one in reverse Watson–Crick mode, providing a structural basis for their function as non-canonical RNA caps." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_UOCHB_Vyzkum_z_UOCHB_odhaluje_dosud_nepoznany_zpusob_prepisu_geneticke_informace_3_4d881e7a58.jpg 245w," sizes="100vw" width="2000" height="1077"><blockquote><h4>The Original article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://www.nature.com/articles/s41589-025-02134-5">Molecular insight into 5′ RNA capping with NpnNs by bacterial RNA polymerase</a></h4>Valentina M. Serianni, Jana Škerlová, Anna Knopp Dubánková, Anton Škríba, Hana Šváchová, Tereza Vučková, Anatolij Filimoněnko, Milan Fábry, Pavlína Řezáčová, Tomáš Kouba &amp; Hana Cahova&nbsp;Nat. Chem. Biol. 21 (2026)<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1038/s41589-025-02134-5">https://doi.org/10.1038/s41589-025-02134-5</a><h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/">CC-BY 4.0</a></h6></blockquote><h4>Abstract</h4>RNA capped with dinucleoside polyphosphates has been discovered in bacteria and eukaryotes only recently. The likely mechanism of this specific capping involves direct incorporation of dinucleoside polyphosphates by RNA polymerase as noncanonical initiating nucleotides. However, how these compounds bind into the active site of RNA polymerase during transcription initiation is unknown. Here, we explored transcription initiation in vitro, using a series of DNA templates in combination with dinucleoside polyphosphates and model RNA polymerase from Thermus thermophilus. We observed that the transcription start site can vary on the basis of the compatibility of the specific template and dinucleoside polyphosphate. Cryo-electron microscopy structures of transcription initiation complexes with dinucleoside polyphosphates revealed that both nucleobase moieties can pair with the DNA template. The first encoded nucleotide pairs in a canonical Watson–Crick manner, whereas the second nucleobase pairs noncanonically in a reverse Watson–Crick manner. Our work provides a structural explanation of how dinucleoside polyphosphates initiate RNA transcription.</div></div>

Research from IOCB Prague reveals a previously unknown mechanism of genetic transcription

In the week of February 9, the following webinars await you in the field of gas / solid phase and especially Raman, FTIR, GC and GC/MS.<blockquote><h4><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinars">👉 DETAILS AND REGISTRATION IN THE WEBINARS SECTION</a></h4>👉 Search and filter in the largest global database with over 5 000 GC, LC, MS and spectroscopy webinars.</blockquote><div><div><div><div><div><div><h5>1. Thermo Fisher Scientific: Process Raman – A Reliable and Versatile Tool for Downstream Process Monitoring and Control for mAb Production</h5><ul><li>Tu, 10.2.2026 16:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/5808">Registration</a></li></ul>The presentation highlights how process Raman spectroscopy offers several advantages over traditional in-line UV-Vis analysis for process monitoring and metabolite production control in mAb manufacturing.<h5>2. Wasson-ECE Instrumentation: The Data Driven Plant – How AI Transforms Chemical Manufacturing</h5><ul><li>Tu, 10.2.2026 21:30 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/5744">Registration</a></li></ul>Explore how artificial intelligence is applied to improve process efficiency, monitoring, and decision-making in modern chemical manufacturing.<h5>3. New Food Magazine: The Science of Next-Gen Ingredients – Fermentation, Formulation and Function</h5><ul><li>We, 11.2.2026 16:00 CET</li><li><a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/webinar/5720">Registration</a></li></ul>Discover how fermentation-driven innovation is transforming functional food ingredients, with analytical insights to optimize flavour, functionality, and product stability.</div></div></div></div></div></div>

Webinars LabRulezGCMS Week 07/2026

This study presents an analytical strategy combining QuEChERS extraction with low-temperature partitioning (LTP) for the determination of multiclass pesticide residues in cocoa beans by GC–MS. Extraction conditions were optimized using a fractional factorial design, resulting in a simple and efficient workflow suitable for complex cocoa matrices.The validated method showed satisfactory limits of detection and quantification, recoveries within 70–120%, and good overall performance. Application to cocoa samples from Brazil detected permethrin in several samples, demonstrating that the QuEChERS–LTP approach is an effective and reliable cleanup strategy for routine pesticide residue analysis in cocoa.<blockquote><h4>The original article</h4><h4><a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360">QuEChERS Combined with Low-Temperature Partitioning and GC–MS as an Analytical Strategy for the Determination of Multiclass Pesticide Residues in Cocoa Beans</a></h4>Priscilla M. de Freitas Machado, Madson M. Nascimento, Paulo R. R. Mesquita, Manuela B. Nascimento, Lilian Lefol N. Guarieiro, Gisele O. da Rocha, Jailson B. de Andrade, Raildo M. de Jesus*ACS Omega 2025, 10, 51, 63464–63473<a target="_blank" rel="noopener noreferrer" href="https://doi.org/10.1021/acsomega.5c10360">https://doi.org/10.1021/acsomega.5c10360</a><h6>licensed under <a target="_blank" rel="noopener noreferrer" href="https://creativecommons.org/licenses/by/4.0/">CC-BY 4.0</a></h6></blockquote>Selected sections from the article follow. Formats and hyperlinks were adapted from the original.Cocoa is best known as the primary raw material for chocolate but is also processed into products such as cocoa butter, biscuits, cocoa honey, and cocoa powder. Cocoa powder is derived from roasted, pressed, and milled nibs, containing on average 20% (w/w) lipids on a dry basis and less than 9% moisture. <a href="javascript:void(0);">(3,4)</a>According to the Brazilian Health Regulatory Agency (ANVISA), pesticides such as atrazine, bifenthrin, cyproconazole, metalaxyl, tebuconazole, trifloxystrobin, and permethrin are approved for use in Brazil. <a href="javascript:void(0);">(13)</a> However, among these, only metalaxyl, trifloxystrobin, and tebuconazole are authorized by the European Union. <a href="javascript:void(0);">(14)</a> Thus, investigating these contaminants in cocoa samples is of utmost importance, as Brazil is one of the largest cocoa exporters, supplying cocoa commodities to South America, the United States, and the European Union. <a href="javascript:void(0);">(2)</a> Furthermore, Organochlorine pesticides, in particular, belong to the class of persistent organic pollutants (POPs). Although banned in many countries, they continue to be used in some developing nations because of their chemical stability, resistance to degradation, volatility, and high lipophilicity, which promote bioaccumulation and neurotoxicity. <a href="javascript:void(0);">(15)</a> Epidemiological evidence also associates their exposure with Parkinson’s disease, certain cancers, diabetes, and endometriosis. <a href="javascript:void(0);">(16)</a>Residues of pesticides in cocoa have been reported in various studies. <a href="javascript:void(0);">(17)</a> Analyzing pesticide residues in cocoa presents analytical challenges due to the matrix’s complexity, comprising high lipid content, fatty acids and esters, sugars, polyphenols, and caffeine. These components can interfere with extraction efficiency and contaminate analytical instrumentation. <a href="javascript:void(0);">(18)</a> Therefore, efficient sample preparation methods incorporating effective cleanup steps are essential for accurate residue determination.Several techniques have been employed for multiresidue pesticide analysis in cocoa. For instance, Idowu et al. <a href="javascript:void(0);">(19)</a> quantified 14 organochlorines using Soxhlet extraction and silica/Na2SO4 cleanup, with GC ECD detection. Okoffo et al. <a href="javascript:void(0);">(20)</a> determined 13 organophosphates and 9 pyrethroids employing SPE cartridges (Envi-carb/LC-NH2 and Bond Elute C18), acetonitrile extraction, and GC PFPD or GC ECD quantification. Yusiasih et al. <a href="javascript:void(0);">(21)</a> applied dispersive SPE with PSA, Florisil, and MgSO4 for pyrethroids, followed by GC ECD and GC–MS.Therefore, this study aimed to evaluate the effectiveness of a QuEChERS–LTP analytical procedure for the determination of multiclass pesticide residues in cocoa beans. The factors that affect the QuEChERS–LTP procedure efficiency were optimized. After validation, the procedure was employed to investigate the occurrence of 15 multiclass pesticides in cocoa samples.<h4>Experimental Section</h4><h5>Instrumental Apparatus</h5>Pesticide separation and identification were performed on a Shimadzu <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=GC-MS-QP2010SE">GC-MS-QP2010SE</a> system (Kyoto, Japan) equipped with an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=1&amp;search=AOC-20i">AOC-20i autosampler</a>. Separation was achieved using an <a target="_blank" rel="noopener noreferrer" href="https://gcms.labrulez.com/library?mainauthorItems=10&amp;search=DB-5MS">Agilent DB-5MS capillary column</a> (30 m × 0.25 mm × 0.25 μm) with a stationary phase of 5% phenyl/95% dimethylpolysiloxane. The instrumental conditions were based on Nascimento et al. <a href="javascript:void(0);">(49)</a> and they are summarized in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#tbl4">Table 4</a>.For quantification, the base peak was used, while two additional ions were monitored for confirmation (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acsomega.5c10360/suppl_file/ao5c10360_si_001.pdf">Table S2</a>) in accordance with SANTE guidelines. <a href="javascript:void(0);">(50)</a> A GC–MS/SIM chromatogram illustrating the separation of all target pesticides is presented in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#fig5">Figure 5</a>.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Omega_2025_10_51_63464_63473_Figure_5_Extracted_ion_chromatogram_EIC_in_SIM_mode_of_the_target_pesticides_f2461c14f4.jpg" alt="ACS Omega 2025, 10, 51, 63464–63473: Figure 5. Extracted ion chromatogram (EIC) in SIM mode of the target pesticides obtained from the injection of a mixed standard solution at 100 μg L–1. Analytes are listed in order of elution: [1] Molinate (6.18 min); [2] α-HCH (8.15 min); [3] atrazine-d5 (8.69 min); [4] atrazine (8.75 min); [5] diazinon (9.31 min); [6] disulfoton (9.67 min); [7] dimethachlor (10.60 min); [8] metalaxyl (11.25 min); [9] p,p′-DDE (15.82 min); [10] cyproconazole I (16.50 min); [11] cyproconazole II (16.56 min); [12] p,p′-DDD (17.29 min); [13] ethion (17.34 min); [14] trifloxystrobin (18.43 min); [15] tebuconazole (19.13 min); [16] bifenthrin (20.47 min); [17] permethrin I (23.92 min); [18] permethrin II (24.18 min)." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Omega_2025_10_51_63464_63473_Figure_5_Extracted_ion_chromatogram_EIC_in_SIM_mode_of_the_target_pesticides_f2461c14f4.jpg 245w," sizes="100vw" width="2080" height="835"><h5>Application of the Proposed Procedure to Real Samples</h5>In a 50 mL Falcon tube, 2.0 g of sample was weighed using an analytical balance (AUX320, Shimadzu, Kyoto, Japan). A total of 2.0 g of salt (NaCl and Na2SO4 in a 1:1 w/w ratio) was added, followed by an aliquot of the atrazine-d5 solution (surrogate standard) to yield a final concentration of 250 μg kg–1. A mixture of acetonitrile (8.0 mL) and ultrapure water (2.0 mL) was then added. The system was vortexed (K40-10208, Kasvi, São Paulo, Brazil) for 3.0 min at 2500 rpm and centrifuged (MPW-351R, MPW Med. Instruments, Warsaw, Poland) for 10.0 min at 15 °C and 10,000 rpm. After phase separation, approximately 6.0 mL of the supernatant was transferred to a Falcon tube containing 150.0 mg of PSA sorbent. The mixture was vortexed again for 3.0 min at 2500 rpm and centrifuged for an additional 10.0 min under the same conditions. The tubes were then placed in the freezer for 24 h. Once the aqueous phase had frozen, the organic extract containing the analytes was collected, filtered through a Cytiva Whatman MiniUniprep G2 vial with a 0.20 μm membrane filter (Marlborough, Massachusetts, USA), and injected into the GC–MS system (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#fig6">Figure 6</a>).<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Omega_2025_10_51_63464_63473_Figure_6_Schematic_representation_of_the_extraction_procedure_using_the_Qu_E_Ch_ERS_LTP_procedure_for_pesticide_extraction_in_cocoa_powder_samples_ed58549bcf.jpg" alt="ACS Omega 2025, 10, 51, 63464–63473: Figure 6. Schematic representation of the extraction procedure using the QuEChERS–LTP procedure for pesticide extraction in cocoa powder samples." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Omega_2025_10_51_63464_63473_Figure_6_Schematic_representation_of_the_extraction_procedure_using_the_Qu_E_Ch_ERS_LTP_procedure_for_pesticide_extraction_in_cocoa_powder_samples_ed58549bcf.jpg 223w," sizes="100vw" width="1458" height="1022"><h4>Results and Discussion</h4><h5>Evaluation of the Effect of Low and Ultralow Temperatures on the Analytical Response</h5>Studies reporting the use of LTP generally employ a conventional freezer, which typically reaches −18 ± 2 °C as the minimum temperature. In this equipment, effective phase separation can require 8 to 24 h. <a href="javascript:void(0);">(35−37)</a> In contrast, ultralow temperature freezers (ultrafreezers) can reach −80 °C, leading to a substantial reduction in partitioning time. In this study, tests performed with the conventional freezer achieved satisfactory partitioning after 24 h, whereas in the ultrafreezer, complete partitioning was observed in only 20 min.Considering the analytical response in terms of peak area (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#fig3">Figure 3</a>), higher signals were obtained when LTP was performed in a conventional freezer rather than an ultrafreezer. This behavior can be attributed to the partitioning mechanism. <a href="javascript:void(0);">(32)</a> Partitioning depends on cooling and the subsequent freezing of the aqueous phase. In the conventional freezer, the slower freezing rate provides sufficient time for the system to approach thermodynamic equilibrium, favoring analyte diffusion between phases. Under these conditions, analyte molecules have more time to migrate and distribute optimally before complete solidification. In contrast, the rapid freezing in the ultrafreezer may trap analytes in a nonideal distribution, reducing the efficiency of the partitioning process <a href="javascript:void(0);">(32)</a> (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#fig3">Figure 3</a>). According to these observations, the conventional freezer was selected for subsequent experiments.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Omega_2025_10_51_63464_63473_Figure_3_Comparison_of_chromatographic_peak_areas_of_pesticides_after_partitioning_in_the_conventional_freezer_versus_the_ultrafreezer_9598bcfec3.jpg" alt="ACS Omega 2025, 10, 51, 63464–63473: Figure 3. Comparison of chromatographic peak areas of pesticides after partitioning in the conventional freezer versus the ultrafreezer." srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Omega_2025_10_51_63464_63473_Figure_3_Comparison_of_chromatographic_peak_areas_of_pesticides_after_partitioning_in_the_conventional_freezer_versus_the_ultrafreezer_9598bcfec3.jpg 175w," sizes="100vw" width="996" height="891"><h5>Application to Real Samples</h5>Fifteen samples were analyzed in triplicate, comprising two from the State of Pará and 12 from the State of Bahia, located in the North and Northeast regions of Brazil, respectively. Among the 15 pesticides investigated, only permethrin isomers were quantified in four samples (<a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#tbl3">Table 3</a>). The herbicide molinate was also detected in three samples; however, its concentration was below LOQ. Permethrin isomers concentrations ranged from 17.1 ± 0.3 to 49.6 ± 1.8 μg kg–1. These values are below the MRL established by European Union regulation, which is 100 μg kg–1. <a href="javascript:void(0);">(42)</a> Although permethrin is not permitted in the European Union, <a href="javascript:void(0);">(42)</a> it remains authorized for use as insecticide in Brazil, particularly in crops such as cotton, rice, coffee, citrus, cabbage, beans, tobacco, maize, soybean, tomato, wheat, and grape. <a href="javascript:void(0);">(13)</a> However, no MRL values have been established for cocoa beans under Brazilian legislation. <a href="javascript:void(0);">(13)</a> <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/10.1021/acsomega.5c10360#tbl3">Table 3</a> shows the concentration of detected compounds in the cocoa samples.<img src="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/ACS_Omega_2025_10_51_63464_63473_Table_3_Mean_Concentrations_mg_kg_1_Standard_Deviation_of_Target_Pesticides_Detected_in_This_Study_2427955699.jpg" alt="ACS Omega 2025, 10, 51, 63464–63473: Table 3. Mean Concentrations (μg kg–1 ± Standard Deviation) of Target Pesticides Detected in This Study" srcset="https://storage.googleapis.com/labrulez-bucket-strapi-h3hsga3/thumbnail_ACS_Omega_2025_10_51_63464_63473_Table_3_Mean_Concentrations_mg_kg_1_Standard_Deviation_of_Target_Pesticides_Detected_in_This_Study_2427955699.jpg 196w," sizes="100vw" width="1070" height="851">To assess method performance for pesticides not detected in the cocoa samples, one of the analyzed samples was fortified with a mixed standard solution at concentrations of 50, 250, and 500 μg kg–1. The fortified analytes were subsequently detected in the chromatograms presented in <a target="_blank" rel="noopener noreferrer" href="https://pubs.acs.org/doi/suppl/10.1021/acsomega.5c10360/suppl_file/ao5c10360_si_001.pdf">Figures S2–S4</a>, indicating good response of the proposed method.<h4>Conclusions</h4>The QuEChERS–LTP procedure was successfully developed for the determination of 16 multiclass pesticide residues in cocoa beans. For the first time, ultralow temperature (−80 °C) was applied to accelerate the low-temperature partitioning process during pesticide extraction from cocoa beans. Nevertheless, conventional freezing at −12 °C proved to be more effective for the extraction of the target analytes.Evaluation of the matrix effect demonstrated that matrix-matched analytical curves, constructed in an analyte-free cocoa bean extract, were more effective in compensating for matrix interferences than the use of analyte protectants.The pyrethroid permethrin was quantified in four cocoa samples. However, the concentrations did not exceed the MRL established by European Union legislation.Overall, the QuEChERS–LTP procedure proved to be a promising approach for pesticide residue determination, as it requires smaller volumes of solvents and reagents, involves fewer cleanup and extraction steps, and shows strong potential for application to other complex matrices.

QuEChERS Combined with Low-Temperature Partitioning and GC–MS as an Analytical Strategy for the Determination of Multiclass Pesticide Residues in Cocoa Beans

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The Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences (IOCB Prague) is a leading scientific institution in the Czech Republic, recognized internationally. Its primary mission is basic research in the fields of chemical biology and medicinal chemistry, organic and material oriented chemistry, chemistry of natural compounds, biochemistry and molecular biology, physical chemistry, theoretical chemistry, and analytical chemistry. 

Institute of Organic Chemistry and Biochemistry of the Czech Academy of Sciences

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Have you ever seen analyte peaks show up in a blank, or extra peaks suddenly appear out of nowhere?
It is likely that you have some carryover or contamination in your system. Contamination that creates ghost and carryover peaks can be introduced at different points, including sample preparation, introduction, and separation. The additional peaks can cause false positive identifications and/or inaccurate quantitative results. 
Join us as we discuss the most common sources of carryover and how to address them.
<blockquote>
Presenter: Alex Ucci (Application Engineer, Agilent Technologies, Inc.)
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In his current position at Agilent, Alex provides application assistance and technical support for sample preparation products as well as GC and LC consumables. Before he joined Agilent in 2014, Alex was a graduate student at the Pennsylvania State University researching the morphology and surface properties of aerosol particles using a wide variety of analytical techniques. He has an MS degree in chemistry.
</blockquote>

Agilent Technologies: Don’t Get Carried Away by Carryover: Troubleshooting GC Chromatography

Don’t Get Carried Away by Carryover: Troubleshooting GC Chromatography

The most common sources of carryover and how to address them.

Troubleshooting GC Chromatography

<h3>PhenoAcademy Webinars - Gas Chromatography Series</h3>
<h4>Gas Chromatography Tips and Tricks</h4>
<ul>
<li>Find new best practices for gas management, and how to keep your system clean
</li>
<li>Identify active sites and impurities within the column and system
</li>
<li>Learn how to properly cut your column, and make the best connections
</li>
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<blockquote>
Presenter: Duilio Romanello (Senior Technical Specialist, Phenomenex)
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<blockquote>
Duilio Romanello graduated with his Bachelors of Science in Pharmaceutical Chemistry and Technology from University of Bologna. Duilio then joined Phenomenex in 2008 as an Inside Technical Sales Consultant becoming Team Leader in Italy for GC/SPE in 2010 and then for the Environmental &amp; Food Team.
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Since 2016 he has been covering the role of Account Manager for the South of Italy working remotely and acting as GC Specialist. Since November 2023 he is Senior Technical Specialist for the Technical team at Phenomenex.
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<blockquote>
Presenter: Zachary Woodward (Senior Technical Specialist, Phenomenex)
</blockquote>
<blockquote>
Zachary Woodward is a Senior Technical Specialist with Phenomenex, Inc, assisting laboratories with method development in the bio-pharma, environmental, and food industries. Zachary spent his formative years developing HPLC and GC methods with a pharmaceutical lab in Albany, NY, after which he developed HPLC and SPE methods in the clinical setting here in Southern California. Zachary received his B.Sci. in Chemistry from the College of William and Mary, was awarded his Master’s in Chemistry at San Diego State University, and is happy to speak with you today!
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<blockquote>
Presenter: Lucia Geis Asteggiante (Senior Technical Specialist, Phenomenex)
</blockquote>
<blockquote>
Lucia is a Senior Technical Specialist that has recently joined Phenomenex’s Global Technical Team. She has a broad experience in the field of Analytical Chemistry with a particular focus on LC chromatography coupled with mass spectrometry. Lucia comes from a strong academic and regulatory background with experiences ranging from method development and analysis of small molecules to large protein complexes. She gained her Ph.D. at the University of Maryland - College Park, USA and did her post-doctoral work at the University of Oxford, UK. During her time as a researcher, she has authored/co-authored 23 scientific publications and 2 book chapters.
</blockquote>

Gas Chromatography Tips and Tricks

Find new best practices for gas management, and how to keep your system clean

Intelligent GCs simplify life inside - and outside - the lab.
Agilent&#39;s intelligent GCs are equipped with robust diagnostic and troubleshooting functions, aimed at minimizing operational downtime. These functionalities are not only accessible locally but can also be efficiently utilized remotely through the built-in browser interface on the Agilent 8860, 8890, and Intuvo 9000 GCs. During our session, we’ll demonstrate specific instances to illustrate how these GCs effectively identify issues and how remote access allows you to address them independent of your proximity to the system. 
When you enable remote operations, you enable faster issue resolution, optimization of your technical resources, and creation of a scalable model for managing instrument schedules and productivity. Why lose time moving your experts from system to system when they could assist technicians in nearby rooms, adjacent buildings, or even across continents from a single location? Join us to explore the extensive diagnostic capabilities of your Agilent GC and bring your queries for an in-depth Q&amp;A discussion.
<blockquote>
Presenter: Jamie Wetuski (Global GC Training Specialist, Agilent Technologies)
</blockquote>
<blockquote>
Jamie Wetuski is the Global GC Training Specialist on the Technical Marketing Team at Agilent Technologies, where she focuses on assisting customers with achieving their GC goals. She began her career at Agilent in the Gulf Coast as a Field Support Scientist servicing Agilent GC/GCMS systems. Jamie received a B.S.in Chemistry from Fort Lewis College in Durango, Colorado and an M.S. in Analytical Chemistry from Illinois Institute of Technology.
</blockquote>
<blockquote>
Presenter: Abbey Fausett (Applications Scientist, Gas Phase Separations Division, Agilent Technologies)
</blockquote>
<blockquote>
Abbey Fausett is an applications scientist within Agilent’s Gas Phase Separation Division. Her responsibilities include developing methods for emerging markets, proving existing methods on new systems, and creating material focused on new features within GC and GCMS systems. Before joining Agilent in 2011, she was an Agilent customer for 10+years, tasked with multi-technique method development, validation, and troubleshooting.
</blockquote>

Agilent: Diagnostics From Your Desk, Troubleshooting From Your Kitchen Table

Diagnostics From Your Desk, Troubleshooting From Your Kitchen Table

Join us to explore the extensive diagnostic capabilities of your Agilent GC and bring your queries for an in-depth Q&A discussion.

Agilent GC Diagnostics and Troubleshooting webinar

Selecting the best GC for you
<blockquote>
Presenter: John Wasson
</blockquote>
<blockquote>
John Wasson has over 40 years of experience in Gas Chromatography and Chemical Instrumentation. He is President of Wasson-ECE Instrumentation, Inc.
</blockquote>

Wasson-ECE Instrumentation: Selecting the Best GC

Selecting the Best GC

Webinar will cover the following topic: Selecting the best GC for you

The Right Laboratory Balance Service at the Right Time
Event Program:
<ul>
<li>Selection of the right instrument for your application</li>
<li>Installation and qualification</li>
<li>Preventive maintenance</li>
<li>Calibration</li>
<li>Routine testing</li>
<li>Replacement</li>
</ul>
Weighing is a core process in almost every application in a lab. To maintain consistent results, it&#39;s essential to regularly service your equipment. But what are the most important services, and how often do they need to be performed?
In this webinar, we will guide you, based on the lifecycle of a balance, through the different services that can help you to keep your instrument accurate and extend its lifetime – from the instrument selection to its installation, throughout its routine operation, and up to the time for replacement.
Join our live webinar with METTLER TOLEDO experts to gain a better understanding.
<blockquote>
Presenter: Simona Venzin (Head of Service Product Management, METTLER TOLEDO)
</blockquote>
<blockquote>
Presenter: Walter Krebs (Head of GWP Product Management, METTLER TOLEDO)
</blockquote>

Mettler-Toledo: Service Balances the Smart Way

Service Balances the Smart Way

A guide through different services that can help you to keep your instrument accurate and extend its lifetime.

Audit Trails are a great tool for troubleshooting and understanding what has happened or changed in your chromatography data system (CDS). If you are in a regulated laboratory, you must also perform periodic review of Audit Trails to ensure data integrity and monitor for impact to the quality of your products, especially entries associated with the results generated for batches of product to be released.
In this webinar, you will gain an understanding of how to use the information captured in the various Audit Trails within Empower Software and in the Empower Message Center. While the Empower Message Center is technically not an Audit Trail and provides information about the Empower Software system, it is imperative that you perform a periodic review of this as well because it contains important information such as instrument and processing errors. We will also demonstrate the Empower Result Audit Viewer, a tool that simplifies review by bringing Audit Trail information for a Result Set into one convenient window.
Topics to be covered include:
<ul>
<li>System Audit Trail</li>
<li>Project Audit Trail</li>
<li>Method Audit Trail</li>
<li>Sample Audit Trail</li>
<li>Sample Set Audit Trail</li>
<li>Result Audit Viewer</li>
<li>Message Center</li>
</ul>
Please join us for a lively discussion as we explore this topic. As always, please bring your questions for this exclusive opportunity to ask our experts anything about Empower Software.
<blockquote>
Presenter: Neil Lander (Principal Product Manager, Informatics, Waters Corporation)
</blockquote>
<blockquote>
Neil has worked for Waters Corporation since 1994 and has held a variety of positions including Technical Support Specialist, Technical Trainer, Manager Customer Education and currently, Principal Marketing Manager focusing on Informatics solutions. He provides internal support for Empower Chromatography Data System and is focused on developing laboratory software solutions that help organizations achieve their scientific and operational objectives. Prior to joining Waters, he was an analytical chemist where he gained experience in both the cosmetics and specialty chemical industries.
</blockquote>

Waters Corporation: Empower Tips: Ask Me Anything About Using and Reviewing Information in Empower Software Audit Trails

Empower Tips: Ask Me Anything About Using and Reviewing Information in Empower Software Audit Trails

Understand how to use the information captured in the various Audit Trails within Empower Software and in the Empower Message Center.

Reviewing Information in Empower Software Audit Trails

Whether you are new to the practice of gas chromatography (GC) or would like a refresher, the installation and care of your GC column is of the utmost importance.
Join us as we discuss proper column installation and handling for all Agilent GCs, including the Intuvo 9000. We’ll also address the common modes of column degradation and some misconceptions that people have concerning column degradation. Lastly, we’ll discuss ways that you can protect and maintain your column’s performance and extend its lifetime while minimizing instrument downtime.
<blockquote>
Presenter: Ryan Birney (Application Engineer, Agilent Technologies, Inc.)
</blockquote>
<blockquote>
In Ryan’s current role at Agilent, he provides application assistance and technical support for GC and Spectroscopy. He has been supporting Agilent in technical and sales roles for the past seven years. Ryan came to Agilent from industry, and has an BS degree in Biochemistry.
</blockquote>
<blockquote>
Presnter: Alex Ucci (Application Engineer, Agilent Technologies, Inc.)
</blockquote>
<blockquote>
In his current position at Agilent, Alex provides application assistance and technical support for sample preparation products as well as GC and LC consumables. Before he joined Agilent in 2014, Alex was a graduate student at the Pennsylvania State University researching the morphology and surface properties of aerosol particles using a wide variety of analytical techniques. He has an MS degree in chemistry.
</blockquote>

Agilent: Becoming a Better Chromatographer

Chromatography Column Care 101: From Setup to Longevity

Join us as we discuss proper column installation and handling for all Agilent GCs, including the Intuvo 9000.

Have you ever had a question about your GC or GC/MS analysis, but it seemed so simple that you thought everyone must already know the answer? We can assure you that you’re not the first nor the last person to ask.
In chromatography, the simplest of questions can have the most complex answers.
<ul>
<li>A question about which liner to use can lead to a discussion on the benefits of glass wool versus glass frits.</li>
<li>A question about how long a column should last triggers a discussion about the importance of a leak-free system, the maximum temperature limit, proper phase selection, and so on.</li>
</ul>
There’s no such thing as an easy answer, often because the answer always “depends” on many factors. To help you improve your chromatographic know-how, we’ve compiled a list of some of our most frequently asked questions. These may seem like simple questions but, in reality, they have anything but simple answers.
<blockquote>
Presenter: Mark Sinnott (Application Engineer, Agilent Technologies, Inc.)
</blockquote>
<blockquote>
Mark Sinnott works for Agilent Technologies as a Technical Support Engineer in the Consumables and Supplies Division (CSD). In his position at Agilent, Mark performs technical support and applications assistance to gas chromatographers worldwide. He has more than 22 years of experience in gas chromatography, including environmental analysis of compounds in air, soil and water matrices, including dissolved gas analysis for the electrical industry. Mark holds a Master’s Degree in Chemistry from California State University, Sacramento, and currently resides in Twin Falls Idaho.
</blockquote>
<blockquote>
Presenter: Vanessa Abercrombie (Gas Chromatography Applications Chemist, Agilent Technologies, Inc.)
</blockquote>
<blockquote>
Vanessa Abercrombie is a GC Applications Chemist at Agilent Technologies in Folsom, CA. Vanessa has a broad background in GC and GC/MS, including experience as an instrument chemist at Bode Technology in Virginia working under contract to the FBI’s Laboratory Division. Prior to that, Vanessa worked for ETS Labs in St. Helena, CA as an Analytical Chemist where she researched and developed quantitative separations by GC/MS and UHPLC for beer, wine and spirits.
</blockquote>

Agilent Technologies: GC and GC/MS Frequently Asked Questions

GC and GC/MS Frequently Asked Questions

To help you improve your chromatographic know-how, we’ve compiled a list of some of our most frequently asked questions.

The evolution of MS continues to push the limits of detection in GC. As source technologies advance, column technology must advance as well. For example, increased detection of analytes also results in increased detection of background like column bleed. Therefore, GC column technology that lowers bleed can enhance your sensitivity and data accuracy.
In this webinar, we’ll examine how column attributes like bleed, thermal stability, and inertness can translate into practical data quality improvements. When used in conjunction with a novel ion source, we’ll illustrate achievable data parameters like sensitivity limits at trace levels, retention time consistencies, and data accuracy for active analytes when combining both column and source technologies.
<blockquote>
Presenter: Vanessa Abercrombie (Gas Chromatography Applications Chemist, Agilent Technologies, Inc.)
</blockquote>
<blockquote>
Vanessa Abercrombie is a GC Applications Chemist at Agilent Technologies in Folsom, CA. Vanessa has a broad background in GC and GC/MS, including experience as an instrument chemist at Bode Technology in Virginia working under contract to the FBI’s Laboratory Division. Prior to that, Vanessa worked for ETS Labs in St. Helena, CA as an Analytical Chemist where she researched and developed quantitative separations by GC/MS and UHPLC for beer, wine and spirits.
</blockquote>

Agilent Technologies: Get the Most Out of Your MS: Novel Column Chemistry Raises the Bar on Sensitivity and Data Accuracy

Get the Most Out of Your MS: Novel Column Chemistry Raises the Bar on Sensitivity and Data Accuracy

We’ll examine how column attributes like bleed, thermal stability, and inertness can translate into practical data quality improvements.

Get the Most Out of Your MS: Novel Column Chemistry

Method development and validation is a time-consuming process that requires the attention of experienced laboratory personnel. There are tools that integrate with Empower Software that dramatically reduce the time needed to build methods, evaluate results, and validate the final method. With these tools you can free up experienced laboratory personnel to carry out other tasks. These tools are compatible with older versions of Empower Software if you have Windows 10.In this webinar we will discuss:<ul><li>Method Developer Application – A new autonomous tool for method screening</li><li>Sample Set Generator – A tool that automates the creation of Instrument Methods, Method Sets and Sample Set Methods for method development and validation</li><li>Method Validation Manager – An Empower Software option that automates chromatographic method validation and performs all necessary statistical calculations</li><li>Scoring Report – A Report Method that scores and ranks the results of method development experiments making it easy to select the optimum separation</li><li>Third-Party AQbD Software – Software that integrates seamlessly with Empower Software to define the experimental region within which changes to method parameters will not significantly affect the separation</li></ul>Please join us for a lively discussion as we explore this topic. As always, please bring your questions for this exclusive opportunity to ask our experts anything about Empower Software.<blockquote>Presenter: Neil Lander (Principal Product Manager, Informatics, Waters Corporation)Neil has worked for Waters Corporation since 1994 and has held a variety of positions including Technical Support Specialist, Technical Trainer, Manager Customer Education and currently, Principal Marketing Manager focusing on Informatics solutions. He provides internal support for Empower Chromatography Data System and is focused on developing laboratory software solutions that help organizations achieve their scientific and operational objectives. Prior to joining Waters, he was an analytical chemist where he gained experience in both the cosmetics and specialty chemical industries.</blockquote>

Waters Corporation: Empower Tips: Ask Me Anything About Tools for Method Screening, Development, and Validation

Empower Tips: Ask Me Anything About Tools for Method Screening, Development, and Validation

In this webinar we will discuss method Developer Application – A new autonomous tool for method screening, sample Set Generator etc.

GCMS webinars focusing on Tips & Tricks - page 7